custom-performance: entire rewrite

Now kills caelestia, change monitor hz and launches lightweight
alternative to calestia (waybar and swaync)

.gitignore

@@ -0,0 +1,9 @@
+# Ignore build outputs from performing a nix-build or `nix build` command
+result
+result-*
+
+# Ignore automatically generated direnv output
+.direnv
+
+# Ignore NixOS interactive test driver history
+**/.nixos-test-history